Mumbai Launches New TBMs as Previous Machine Remains Abandoned Underground
As Mumbai initiates the launch of two new giant Tunnel Boring Machines (TBMs) for major infrastructure projects, a German-made TBM remains abandoned 60 meters beneath Powai. The machine, deployed by the Brihanmumbai Municipal Corporation (BMC) for a water conveyance tunnel, became trapped in volcanic ash and monsoon sludge in 2019. Despite repeated retrieval attempts, heavy flooding in 2020 made extraction impossible, leading the BMC to write off the Rs 32 crore cost. This unprecedented engineering failure caused significant project delays and a cost escalation of Rs 419 crore. To complete the remaining 2.7 km stretch, the BMC procured a new TBM and utilized the New Austrian Tunneling Method (NATM) for difficult soil sections. While the city continues to expand its underground network for Metro lines and water systems, the entombed machine serves as a stark reminder of the geological challenges faced during urban infrastructure development. The incident highlights rare global occurrences of TBM failures, comparable to the Seattle Bertha incident, yet unique in its permanent abandonment due to local environmental conditions.
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Mumbai Launches New TBMs as Previous Machine Remains Abandoned Underground
As Mumbai initiates the launch of two new giant Tunnel Boring Machines (TBMs) for major infrastructure projects, a German-made TBM remains abandoned 60 meters beneath Powai. The machine, deployed by the Brihanmumbai Municipal Corporation (BMC) for a water conveyance tunnel, became trapped in volcanic ash and monsoon sludge in 2019. Despite repeated retrieval attempts, heavy flooding in 2020 made extraction impossible, leading the BMC to write off the Rs 32 crore cost. This unprecedented engineering failure caused significant project delays and a cost escalation of Rs 419 crore. To complete the remaining 2.7 km stretch, the BMC procured a new TBM and utilized the New Austrian Tunneling Method (NATM) for difficult soil sections. While the city continues to expand its underground network for Metro lines and water systems, the entombed machine serves as a stark reminder of the geological challenges faced during urban infrastructure development. The incident highlights rare global occurrences of TBM failures, comparable to the Seattle Bertha incident, yet unique in its permanent abandonment due to local environmental conditions.
indianexpress